This is a collaborative project that focuses upon the mass spectral characteristics of the 1,2-alkylenedioxy-benzofurazans and -benzofuroxans, which are classes of compounds that have pharmacological importance. The compounds of interest produce ions that are diagnostic to the configuration, whether linear or angular. We provided expertise in high-resolution mass spectrometry which verified the formulas of these and other fragment ions. We also performed high-resolution parent-ion scans to ascertain the origins of ions of configurational distinction along with CAD and MI MS/MS experiments to determine fragmentation patterns and relationships of ions in the EI mass spectra of these compounds. From information provided by these experiments, schemes of fragmentation for these classes of compounds have been proposed, which would add to the mass-spectral knowledge base. We have also applied molecular orbital calculations and molecular modeling to understand the frag ment ations of this class of compounds, which maybe medicinally useful.